3x - 13 = 7(x + 2) -4 (x -7)
3x - 13 = 7(x + 2) -4 (x -7) simplify the right side
3x - 13 = 7x + 14 - 4x + 28
3x + 13 = 3x + 42 this has no solution........we can't add two different quantities to 3x and expect the same result!!!!
